CVE-2023-54233: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-54233 is a NULL pointer dereference vulnerability in the Linux kernel's ASoC (Audio System on Chip) SOF (Sound Open Firmware) subsystem. It occurs when an IPC4 topology contains an unsupported widget whose .module_info field is not initialized, causing a kernel Oops in sof_ipc4_route_setup(). The vulnerability was published on December 30, 2025, and affects Linux kernel versions from the initial commit up to (but not including) the patched commits e3720f92e023 and 170818974e97. No CVSS base score has been assigned at this time, and the EPSS score is approximately 0.026% (Feedly, EUVD).

The root cause is a missing NULL check (CWE-476: NULL Pointer Dereference) in the sof_ipc4_route_setup() function within the Linux kernel's ASoC SOF IPC4 driver. When an IPC4 audio topology is loaded containing a widget type not supported by the driver, the widget's .module_info field is left uninitialized (NULL). A subsequent attempt to dereference this pointer during route setup triggers a kernel Oops, crashing the affected subsystem. The fix adds an explicit check for unsupported widgets before dereferencing .module_info (Feedly, Kernel Patch 1, Kernel Patch 2).

Successful triggering of this vulnerability causes a kernel Oops (panic/crash) in the ASoC SOF subsystem, resulting in a denial of service for the affected system or audio subsystem. The impact is primarily an availability concern — an attacker or user who can load a malformed IPC4 audio topology could crash the kernel. There is no known confidentiality or integrity impact, and lateral movement potential is minimal given the localized nature of the audio driver crash (Feedly).

The Linux kernel maintainers have addressed this vulnerability in two stable-branch patches: commit e3720f92e023 (patched in kernel 6.2.11) and commit 170818974e97 (patched in kernel 6.3). Users should update to Linux kernel version 6.2.11 or 6.3 or later to remediate this issue. As a workaround, avoiding the use of unsupported IPC4 audio topologies on affected systems can prevent triggering the NULL dereference (Feedly, Kernel Patch 1, Kernel Patch 2).